etabs_define_material

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already establish this as a non-read-only, non-destructive, non-idempotent, closed-world mutation, so the safety profile is covered. The description usefully notes that library inputs mirror the 'Add Material' dialog, but it omits what happens if the material name already exists, whether overwrite/error occurs, and any permission or model-state requirements.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

A single sentence, front-loaded with the core action, that covers both modes without redundancy. No filler and no restatement of the tool name.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a 12-parameter mutation with an output schema, the description covers the essential branching but is thin on preconditions, duplicate-name behavior, and where it sits in the define-then-assign workflow. Adequate as a minimum-viable definition, with clear gaps an agent would hit in practice.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The description groups parameters by creation mode (library vs custom), which clarifies intent, but the schema already labels region/standard/grade as 'Library material' and elastic_modulus as 'Custom material'. Beyond that grouping, 12 parameters at 67% coverage leave defaults and interactions (poisson_ratio, thermal_coefficient, fu default of 1.25 fy, mixing library and custom fields) unexplained.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a specific verb and resource ('Define a material') and, unusually, explains the two distinct creation paths: library (region + standard + grade) and custom isotropic (E, weight, strength). It does not, however, position itself against nearby siblings such as etabs_define_frame_section or etabs_define_area_section, which consume materials once defined.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It gives a usable branch between library and custom input but frames this as parameter selection rather than tool-selection guidance. There is no statement of prerequisites (an open/unlocked model, units) or of when-not to call it, so an agent must infer the workflow position.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.